Sry to just now get back to this guys.
What I did was take a piece of 3/4" plate, the same dimensions as the back side of bucket ( about 18" x 60" ?) or so. I then formed up some U channels from 1/4" flat material, about 12" long, with the i d of the channel just a little larger than the clevis of my loader arms. Then I drilled some 1" holes for the loader pins,and also welded some short (1/2" long) bushings on each side of the channel to give it some more support then the 1/4" channel would allow, and then welded these 2 channels to the back of the plate vertically. I welded some 3x3x1/4" angle iron at the top and bottom of the plate, between the channels, again just copying the design of my loader bucket. I had to make some longer pins out of some 1" shafting, but then I also cut snap ring grooves to hold the pins in and drilled grease holes and fittings in the pins to allow me to grease the pins and the loader fittings and the channel.
Before I installed the plate on the loader arms, I drilled a 2" hole about 4 inches from the top, right in the center (from rt to left), then I drilled two 1 1/4" holes about 4 inches from the bottom, about 30" apart. These were for my bale spears. I then made some spears on my lathe, from 2 1/2" 4140 and machined a point on one end and turned the other end down to fit through the 2" hole in the plate, and cut threads on the shaft (spear) for a 2" nut. I then did the same thing for the other holes, using 1 1/2" shafting and cutting 1 1/4" threads on the other end, opposite the point. I slide the spears through the holes and put on some big washers and big nuts, and it's worked great so far! Knock on wood!!
As far as the forks, I picked up some old forks from a forklift dealer we do some work for, and machined the top and bottom of the plate to fit the forks, The forks had a cap welded on top of them to keep them from falling forward and falling off the forklift mast. The gap between the fork and the welded cap on top was just over 5/8", so I had to mill the top and bottom edges of my plate to allow the forks to slide onto the plate. It really sounds alot more complicated than it was.
Granted, owning a big machine shop enabled me to do these things, but if you bought the materials and did the welding yourself, there probably wasnt 4-5 hrs machine shop work involved. I knocked it out in a couple evenings. 4-5 hrs machine shop work = about $200 And if you get your forks first, then you could just buy a plate that allows the forks to slide on it, thereby knocking off most of the machine work. The plate for the bale spears was mostly just welding, other than
making the spears (3 spears in about an hr) and the bushings. So the bale spear part could be done for about $100 if you had access to a large plate and a cutting torch.
My wife has a digital camera, so I'll see if we can get a couple pics on here. I cant post them, but I can send them to TxAg or CertHerf and they know how to post pics.